The resolution, negotiated off and on for months, is under Chapter 7 of the U.N. Charter, which means it can be militarily enforced. African members of the 15-member council had expressed concern about that.

The resolution also authorizes the European Union and individual nations to board vessels "with a view to saving the threatened lives of migrants or of victims of human trafficking."

The International Organization for Migration says that more than 2,600 migrants have died in 2015 so far on the Central Mediterranean route that includes Libya.

The resolution authorizes the search and seizure operation for one year. It says migrants "should be treated with humanity and dignity."

Council diplomats have said migrants on vessels that are searched and seized would be taken to Italy.

The resolution underscores that the intention is not to prevent individuals from exercising their human rights or prevent them from seeking protection.

The EU initially wanted a naval operation in Libyan territorial waters and along its coast, but Libya objected. Its approval is needed for such an operation, but the North African country remains divided between two rival governments that the U.N. is trying to lead into a final peace deal.

Smugglers have exploited the chaos in the country to launch often flimsy boats full of migrants and refugees toward Europe. Many people have died along the way.

The original draft of the resolution would have authorized the destruction of the vessels, but the resolution states that any action on disposal of a seized vessel must be taken in accordance with international law "with due consideration of the interests of any third parties who have acted in good faith."